A wind turbine is an energy conversion system which converts kinetic wind energy into electrical energy for utility power grids. Specifically, wind incident on blades of the wind turbine generator (WTG) causes a rotor of the WTG to rotate. The mechanical energy of the rotating rotor in turn is converted into electrical energy by an electrical generator.
A wind power plant is often referred to as a group of wind turbine generators which are commonly connected to an electrical grid through a common connection point, also known as Point of Common Coupling (PCC). Additionally the wind power plant may comprise a power plant controller (PPC) and/or some sort of reactive power compensation equipment, such as STATCOMs or switch capacitors, or others.
Due to the advancements in the grid code requirements and more wind energy entering into the electrical grid, there is an important need for wind turbine generator and especially wind power plant to be able to provide the support required by the grid whenever necessary. Voltage stability is seen to be the major problem in many power systems especially at the location of the wind power plant. Hence, the wind power plant and its wind turbine generators should be able to provide advanced support which can be comparable to that of the traditional synchronous machine with respect to the voltage support.